weinerschizel

I have a 2001 Tahoe. Just bought it and the parking break didn't work. So I replaced the shoes yesterday which were obviously bad and the fine adjustment screws / expander screws. The star had broken off each of them where you put the wrench to adjust the shoe size.

I adjusted the shoe's size till the hat in the rotor just fit over them. Then I put everything back together. Lastly I adjusted the break line cable to it's minimum length.

The parking break cable still hits the floor with very minimal resistance and the break does not engage fully.

I cannot see any breaks in the cable. So I asked a couple mechanic friends, they say they've never seen those cables stretch.

I'm at a loss any ideas?

Patsgarage

I would start by having a friend apply the parking brake while you watch the cable entering the rear wheels. If the cable is moving fully back there the problem is inside the wheel, if not then work your way towards the front until you see where the slack is being taken up. I agree with your friends, the cables should be OK.

leadfoot4

Is this one of those parking brakes with shoes inside of a rear brake rotor? If so, set the clearance between the shoes (when retracted) and rotor to 0.015". That's what it took, to hold my Jeep Grand Cherokee from moving, when the vehicle was in "drive", but without applying throttle.

weinerschizel

This was very helpful. I set my cell phone under the cable and recorded pressing the parking break. I noticed one side had a lot of slack in it yet. Turns out the rotor, inner hat, had a large grove in it. It was too far warn.

It helped but car still rolls when I'm on a hill in neutral with parking brake on. and there's still slack on the same side I replaced.

Leadfoot4: how did you measure the gap between the shoe and the hat? I have no clue how to get anything inside there to measure it. I'm just adjusting till it's hard to get on, yet spins without much resistance once hat is fully on the hub.

Patsgarage

Can you get a feeler gauge between the rotor and shoes ?

leadfoot4

Brake shoe adjusting tools come in a couple of sizes. There are the somewhat larger ones, designed to be used on old style drum brakes, and there are now smaller ones, designed to be used for either adjusting drum brakes on "econo-boxes" that have tiny brakes, or like my Jeep, that have shoe-style parking brakes, that have a drum inside the rear rotor. (I bought my tool on Amazon)

I set the tool to the ID of the parking brake drum, then set the shoes so there was a slight drag of a 0.015" feeler gauge between the shoes and the jaws of the adjusting tool.

weinerschizel

Shucks, what a PITA lol There's no tools for this brake, and no way to get a gauge in there to measure it. I discovered, the design is such that the driver side interferes with a control arm bracket for the rear axle.

I've adjusted till I needed a tire iron between the lugs to turn the hub on that side once the drum was back over the shoe. I think the other side needs adjusted yet too. However...

I see despite adjusting so tight the lever still interferes with the bracket. Curious if this is the case with other people who have GM truck products of this design....





Passenger side doesn't have a bracket to interfere with.



Driver side brake and parking brake lever. Lever interferes with bracket to right.



Parking brake lever. Interferes with bracket on axle.

leadfoot4

I would think, that before the cable has pulled the lever THAT FAR, you should have full engagement of the shoes against the inside of the rotor. Therefore, I would think, that the p-brake shoes aren't adjusted properly.

weinerschizel

thanks, I took the cable off as well and played with that level when the shoe is on. The movement of the brake is extremely minimal with that lever. I see the side opposite the adjuster moves out, the side with the little metal pin in it.

I did this adjustment on my corvette it was a super easy. However, I'm doing same thing on this car and having all kinds of problems. I'm not sure where I'm going wrong.

The hat barely fits over the shoe. I can barely slide the hat on. I have to bang it hard with my hands a bunch of times. Then it slides on. Once it's on I have to use leverage to turn the axle.

Before putting the cable back onto the parking brake anchor, lever, I moved that lever with my fingers. It moves about a 1/2 that distance before hitting the hat. Once I put the cable on and use the brake it moves the full distance hitting the bracket

leadfoot4

I used the Ampro T71558 adjusting gauge (purchased on Amazon), to measure the diameter of the "drum" inside the rotor I then adjusted the shoes, so they had a snug fit between the gauge and a 0.015" piece of feeler stock. The problem you're having, initially sliding the rotor over the p/b shoes, is most likely caused by rust build-up on the OD of the "drum", as the rotors aren't painted, and the portion that doesn't see the friction from the brake shoes, rusts up. I suggest getting some coarse sandpaper, and knocking down the rust.

Patsgarage

I have what might be a stupid question, but is there a lip on the inside of the rotor ? I know you replaced one of them, but what about the other side ? The inner surface should be even all the way across. I agree with Leadfoot4, the brakes should be tight way before the cable moves that far.

leadfoot4

Something just crossed my mind....what kind of shape are the p/b shoes in? I know that they shouldn't be thin, as in worn out, because all they're supposed to do is hold the vehicle after it's been parked. But on the odd chance that they were incorrectly adjusted initially, and were dragging on the inside of the rotor, they could now be "thin" enough that the normal range of travel, isn't sufficient to get them to engage properly. Just a wild thought...

weinerschizel

Hi ledfoot4 and patsgarage: Thanks much for the suggestions. Both rotors are new. I pulled it all back appart and both shoes are looking new yet too. They have a little wear at the ends of the material in the direction of travel but middles were looking new yet.

I finally got it working but don't believe it should have been this tricky to adjust. I litteraly pulled it all apart. One culpret was the shoes were not of good quality. the ends of the shoes, where they mate with the adjustment screws, was not flat... this was causing them to climb over the shoe (pushing them larger) when the rotor / hat was put back on. I switched them the other way and the lower edge of the shoe caught on the edge of the adjustment screw.

Next I tore apart the leaver on the side that was interfering. This lever is suspect. I will put a video at the bottom. It doesn't slide consistently in the track. I noticed if there isn't much pressure on the shoe (hat is off) it can clear the bracket on the axle. I think it maybe warn out or missing something. I may go to the parts store and see if they'll let me look at a new one.

Lastly, as I mentioned I got it working. I literally adjusted that side to the point I had to use a rubber mallet to get the rotor back on. Then the hub wouldn't turn at all, just barely using the tire iron for leverage.

I drove the truck slowly for a mile. Then applied the parking brake, I drove in reverse with the parking brake on, and blipping the gas, then hitting the brake hard and releasing the parking brake. I think this may help the self adjuster?

Lastly I did the other side again tightening it even further and repeating the self adjustment process.

It worked. However, I'm thinking that lever on the parking brake anchor plate shouldn't interfere at all. I think it's warn out somehow. You'll notice in the video it can jog around the bracket without interfering when releasing the parking brake.

Video of lever when applying the parking brake

Video of lever when releasing the parking brake



Slot the lever fits into. I removed it to clean and inspect. Only noticeable thing is the rubber is warn out but not a big deal.



The lever will only fit in through a grove in the slot on the right hand side. However, it had a lot of wiggle room once in there. Which is odd to me. I almost felt like there should be a plug in that slot it installs through. but not sure. The other side / wheel was the same setup.